A heart murmur is a clinical finding that is most often discovered during occasional visits, and until then the carrier is unaware of it. So it is not actually a disease or a symptom, but rather a noise audible to the specialist by auscultating the heart with a phonendoscope.
Normally, the flow of blood within blood vessels (arteries and veins) or heart chambers (atria and ventricles) occurs silently by so-called laminar flow, through conduits with smooth walls and no obstructions to flow.
